Generalizations of the real and complex number systems

How to read commutative diagrams

An introduction to commutative diagrams, a compact language for describing algebraic objects and structure-preserving maps between them.

Naïve set theory

A quick overview of elementary set theory, covering the basic terminology, relations and functions, equivalence relations and quotient sets, cartesian produc...

Killing the hydra

20 m

On Kirby–Paris Hydra game, which involves killing off a particularly vicious modern variant of the Lernaean Hydra